Copying apparatus

ABSTRACT

A copying apparatus in which thin or thick originals such as individual sheets or thick books are selectively driven over an illumination slit aperture, characterized by a transparent book support such as a glass plate connected to a known transport mechanism for individual sheets such as a pair of transport rolls. The book support is located on the extension of the transport mechanism, and the transport mechanism and the book support are selectively movable together.

United States Patent [191 Knechtel et al.

COPYING APPARATUS Inventors: Wilhelm Knechtel, Biebertal;

Gerhard Petersdorf, Pohlheim/W-Stbg; Winfried Sandner, Rechtenbach, allof Germany Assignee: Canon Kabushiki Kaisha, Tokyo,

Japan Filed: Feb. 11, 1972' Appl. No.: 225,483

Foreign Application Priority Data Feb. 16, l97l Germany P 2107 321.2

US. Cl. 355/50 Int. Cl. G03b 27/32 Field of Search 355/8, 50, 51, 64,

111 3,741,646 1 June 26, 1973 [56] References Cited UNITED STATESPATENTS 3,510,218 5/1970 Limberger .3S5/5l Primary Exqminer John M.Horan Attorney-Joseph M. Fitzpatrick, John Thomas Celia et a].

[57] ABSTRACT A copying apparatus in which thin or thick originals suchas individual sheets or thick books are selectively driven over anillumination slit aperture characterized by a transparent book supportsuch as a glass plate connected to a known transport mechanism forindividual sheets such as a pair of transport rolls. The book support islocated on the extension of the transport mechanism, and the transportmechanism and the book support are selectively movabletogether.

7 Claims, 2 Drawing Figures PATENTEI] JUN 26 I975 SIIEIIUFZ COPYINGAPPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention Thisinvention relates to a copying apparatus in which twoor threedimensionaloriginals such as individual sheets or thick books are selectivelydriven over an illumination slit aperture.

2. Description of the Prior Art In the copying apparatus of thedescribed type, the slit aperture is projected, for example, on a drumcarrying photosensitive paper thereon. The speed of rotation of the drumis made equal to the speed at which the originals are moved over theslit aperture. The images of the originals guided over the slit apertureare successively exposed onto the photosensitive paper on the drum.Thereafter, the photosensitive paper can be developed in a subsequentdeveloping device in a known manner.

Such a copying apparatus has an advantage that both individual sheetsand desired book pages can be copied. However, the operation of suchapparatus is troublesome because the original is usually placed on aglass plate which is movable over the slit aperture, which glass platemust be covered in order not to dazzle the user. Accordingly, toposition the original, a cover or a flap cover must first be opened sothat the original can be placed on the glass plate,- whereafter thecover or the flap cover must be shut again. The same procedures arerequired to remove the original. In addition, the original must beplaced within a predetermined field on the glass plate in accordancewith its size, so that copying with such apparatus is troublesome andtime-consuming.

There is also known a device in which the originals, when they areindividual sheets, are directly inserted into a guide groove in thedevice and gripped by transport rolls so as to move through the device.In this case, one can successively introduce individual sheets asoriginals into the device, thereby enabling quick and simple copying totake place. However, this device does not permit copies of books to beobtained.

Accordingly, it has already been proposed that for copies of individualsheets, two sets of transport rolls be used to guide the sheets over theillumination slit aperture and that for copies of desired book pages,the upper rolls of the transport mechanism for individual sheets bedetachably arranged and a glass plate with a book resting thereon beguided by utilizing the remaining lower transport rolls of the transportmechanism. The remaining lower transport rolls are frictionallyengageable with the glass plate to ensure the automatic transportthereof.

This arrangement has the disadvantages that, to obtain copies of books,part of the apparatus must be detached to change the constructionthereof and, moreover, the detached apparatus part must be placedsomewhere else during copying.

SUMMARY OF THE'INVENTION The object of the present invention is toprovide a novel copying apparatus which enables both twodimensional andthree-dimensionaloriginals such as individual sheets or book pages to becopied without changing the arrangement of the apparatus in any waywhile maintaining simplicity and quickness of the copying, andparticularly permits individual sheets used as originals, to becontinuously introduced into the apparatus.

Such object of the present invention can be achieved by a copyingapparatus of the type described at the beginning hereof in which atransparent book support, preferably in the form of a glass plate, isconnected to a known transport mechanism for individual sheets,preferably in the form of a pair of transport rolls, the book supportbeing located on the extension of the transport mechanism for individualsheets, and the transport mechanism for individual sheets and the booksupport being selectively movable together.

According to the construction of the present invention, individualsheets are guided for copying to the transport rolls, which move thesheets to pass over the illumination slit aperture. Thus it is possibleto introduce the successive sheets continuously into the apparatus as inthe aforesaid known system. In this case, the transport mechanism andthe book support remain stationary in their positions.

When certain pages of a book are to be copied, the book is opened andplaced on the glass plate, then the transport mechanism for individualsheets is moved together with the book support so that the glass platewith the book thereon is guided over the illumination slit aperture.

In a preferred embodiment of the present invention, the book support canalso serve as guide to insert individual sheets into a first set oftransport rolls.

The common movement of the transport mechanism and the book support canbe accomplished mechanically. However, such construction requires anadditional cost, so that in a preferred embodiment of the presentinvention, therefore, the book support and the transport mechanism forindividual sheets are arranged so as to be manually movable.

In this case, care must be taken so that the speed of such movement maybe in accord with the speed of rotation of the drum, for example,because the image of the original would otherwise be distorted. In orderto achieve this, according to another preferred embodiment of thepresent invention, the transport mechanism for individual sheets isdesigned so that it is driven by a motor which in turn acts as a brakingdevice for limiting the speed of the book support which is manuallymovable.

In the construction of this preferred embodiment, operation is effectedas follows: If the book support is moved too fast, a free wheel willform a rigid connection between the book support and a chain driven bythe drive motor when a predetermined limit speed is reached. In otherwords, if this limit speed is exceeded, the motor will brake thepressure manually applied to the book support. This brake force isclearly sensed by the user so that it becomes very easy for the user toexto move the image-receiving drum, the transport mechanism forindividual sheets and the free wheel for moving the book support insynchronism. Conveniently, the chain of the drive motor for driving thetransport mechanism for individual sheets may be engaged with the drivegear of the free wheel at the same time.

Preferably, the shaft for the free wheel is fixedly mounted to the booksupport.

According to stillanother embodiment of the present invention, theaforesaid free wheel may be replaced by a coupling. With the aid of thiscoupling, automatic movement of the book support can be effected. Indecoupled position, individual sheets are copied and the return of thebook support is accomplished manually.

The book support and the transport mechanism for individual sheets areheld in a start position by lock means which preferably function underthe action of a spring. A smaller manual pressure on the book supportwill suffice to permit movement of the book carrier.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described indetail with respect to embodiments shown in the accompanying drawings,in which:

FIG. 1 is a schematic view, in longitudinal section, of the copyingapparatus; and

FIG. 2 is a partly cut-away side view of the appatatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Individual sheets to be copiedare inserted between a pair of transport rolls 1. from above a glassplate 2. The transport rolls 1 guide the inserted individual sheets overanother glass plate 3 to another pair of transport rolls 4, whichdischarges the originals passed through the transport unit 1, 3, 4 ontoa table 5. In the position shown in FIG. 1, the image of the originalwhich moves over the glass plate 3 is projected through a mirror 6, anobjective lens 7 and a mirror 8 disposed just behind the objective lensonto a segment A of a drum 9. The illumination of the glass plate 3 and,accordingly, of the original is carried out by two light sources 10 and11, to which mirrors 12 and 13 are disposed to correspond.

The drum 9 is rotatable in the direction of arrow 14. The drum 9 isdriven by a motor 15 for driving a chain 16 as shown in FIG. 2. Thechain 16 is engaged with a gear 18 of the drum and moves in thedirection of arrow 17. The chain 16 is further engaged and guided by areadily braked gear 19 fixedly positioned and rotatably mounted in theapparatus. As will be described, along the path of the chain 16,there-are further disposed a gear 20 of a free wheel clutch device 21, atension wheel 22 and a gear 23, via which the chain is guided .in thedirection of arrow 24. An unshown deflection gear'then brings the chain16 back to the gear 18 of the drum 9, thus driving it in an endlessmanner. In order to equalize the speed of rotation of the drum 9 to thatof movement of the original between the transport rolls 1 and 4, thegear 23 is connected to another gear 25 mounted on the same shaft. Thisgear meshes with a gear 26. The gear 26 is mounted on the shaft whichcarries the lower one of the set of transport rolls 1, so as to rotatethat particular roll at a reduced speed selected to equal the speed ofrotation of the drum 9. Mounted on the shaft of the gear 26 is anothergear 27 which is engaged via a chain 28 with a gear 29 for rotating thelower one of another set of transport rolls 4. Thus, the transport rolls4 at the outlet side are rotated at the same rotational speed as thetransport rolls 1 at the inlet side.

In order to permit the inserted individual sheets to move over the glassplate 3 without hindrance, the edge 30 of the glass plate 3 adjacent tothe inlet side is downwardly inclined. The transport unit 1, 3, 4,including the first glass plate 2, is housed in a casing 31. The casing31, having the glass plate 2, transport unit 1, 3, 4 and table 5, isreciprocally movable on a roll track 33 fixedly provided in theapparatus, in the direction of arrow 34. During the movement of thecasing, the gears 20, 22 and 23 move on the chain 16.

To copy desired pages of a thick book 35, it is opened at the pages tobe copied and placed on the glass plate 2. Then the book is guided overthe illumination slit aperture 36 so that the images of the pages to becopied are projected on the drum 9. In the start position shown in FIG.1, a lever 37 pivotable about the shaft 36' has its projection 38received in a corresponding groove 39 formed in the casing 31 so thatthe casing 31 is held in its start position. The movement of the glassplate 2 and the aforesaid transport unit connected thereto is carriedout by manually in the direction of arrow 40. The lever 37 is under theaction of a spring 41 so that the projection 38 of the lever isdisengaged from the groove 39 simply by pushing the plate slightly.

The free wheel 21 has a shaft 50 fixedly mounted in the casing 31, andon the shaft 50 is seated a wheel 51 which carries the gear 20. Thewheel 51 has progres sively enlarged cut-outs S2 in which balls 53 arereceived respectively.

When the glass plate 2 is at rest, the gear 20 is continuously rotatedby the moving chain 16. The balls 53 are then in abutment with thewidest end portions of the cut-outs so that no rotational moment isapplied to the shaft 50. When the glass plate 2 is moved in thedirection of arrow 40, the condition described above is maintained aslong as the speed of movement of the glass plate is lower than the speedof movement of the chain 16. If the speed of movement of the glass plate2 reaches the speed level of the chain 16, then the balls 53 are pressedto go toward the narrower ends of the cut-outs 52, thereby creating arigid connection between the wheels 51 and 50. As the result of such arigid connection therebetween, the glass plate 2 can not move in thedirection of arrow 40 faster than the speed of movement of the chain 16.Thus, a braking force is applied at the synchronous speed of the drum 9and casing 31.

According to the arrangement described above, it is ensured that theglass plate 2 be moved'exactly in synchronism with the speed of rotationof the drum 9. When the glass plate 2 with a bo'okthereon is guided overthe-illumination slit aperture 36 and copying has been completed, theplate 2 can be returned to its start position without any difficulty.During this return movement, the free wheel imparts no brake force tosuch return motion, because the balls 53 are now again positioned towardthe widest end portions of the cutouts 52. v

We claim:

1. Photocopying apparatus comprisinga housing, exposure slit meansfixedly mounted on said housing, a transparent support member forreceiving thereon a thick original to be copied, sheet originaltransporting means including at least one pair of opposed rollersoperable to move a sheet original past said exposure slit means, acasing movably mounted on said housing and having said support memberand sheet original fixedly connected thereto wherein said support membercan be moved past said exposure slit means, means for releasably holdingsaid casing in a fixed position while said sheet original transportingmeans operates to move a sheet original past said exposure slit meansand for releasing said casing for said movement on said housing when athick original is to be copied, driving means coupled to one of saidopposed rollers to impart rotational movement thereto, and clutch meansmounted on said casing and coupled to said driving means for allowingsaid casing to remain in said fixed position while a sheet original isbeing copied and to maintain the speed of movement of said casing insynchronism with the speed of movement of said driving means when athick original is being copied.

2. Photocopying apparatus according. to claim 1, wherein said clutchmeans comprises a'shaft fixedly mounted to said casing and meansengaging said driving means for free rotation only in one direction withrespect to said shaft and being fixed with respect to said shaft to stopthe rotation thereof when said casing is moved to copy a thick original.

3. Photocopying apparatus according to claim 2, wherein said drivingmeans includes a chain, and wherein said engaging means comprises awheel provided to be rotatable around said fixed shaft and having teethfor engaging said chain, said wheel having a plurality ofcircumferentially extending openings communicating with said shaft andeach said opening being tapered at its outer periphery to provide a wideportion and a narrow portion, and a plurality of balls respectivelyreceived in said openings to be rotatable at said wide portion whileconfined to fix said wheel to said shaft at said narrow portion.

4. Photocopying apparatus according to claim 2, wherein said engagingmeans includes a wheel mounted on said shaft and provided with a gear,and wherein said driving means comprises a chain in mesh with said gear.

5. Photocopying apparatus according to claim 1, wherein said casing ismounted for being manually returned to its said fixed position aftercompletion of its movement.

6. Photocopying apparatus according to claim 1, wherein said transparentsupport member for said thick original is mounted to provide a guidemember for a sheet original inserted into said sheet originaltransporting means.

7. Photocopying apparatus according to claim 1, wherein said means forreleasably holding said casing comprises a projecting member resilientlymounted on said housing, and wherein said casing defines a recessed areafor releasably receiving said projecting member.

1. Photocopying apparatus comprising a housing, exposure slit means fixedly mounted on said housing, a transparent support member for receiving thereon a thick original to be copied, sheet original transporting means including at least one pair of opposed rollers operable to move a sheet original past said exposure slit means, a casing movably mounted on said housing and having said support member and sheet original fixedly connected thereto wherein said support member can be moved past said exposure slit means, means for releasably holding said casing in a fixed position while said sheet original transporting means operates to move a sheet original past said exposure slit means and for releasing said casing for said movement on said housing when a thick original is to be copied, driving means coupled to one of said opposed rollers to impart rotational movement thereto, and clutch means mounted on said casing and coupled to said driving means for allowing said casing to remain in said fixed position while a sheet original is being copied and to maintain the speed of movement of said casing in synchronism with the speed of movement of said driving means when a thick original is being copied.
 2. Photocopying apparatus according to claim 1, wherein said clutch means comprises a shaft fixedly mounted to said casing and means engaging said driving means for free rotation only in one direction with respect to said shaft and being fixed with respect to said shaft to stop the rotation thereof when said casing is moved to copy a thick original.
 3. Photocopying apparatus according to claim 2, wherein said driving means includes a chain, and wherein said engaging means comprises a wheel provided to be rotatable around said fixed shaft and having teeth for engaging said chain, said wheel having a plurality of circumferentially extending openings communicating with said shaft and each said opening being tapereD at its outer periphery to provide a wide portion and a narrow portion, and a plurality of balls respectively received in said openings to be rotatable at said wide portion while confined to fix said wheel to said shaft at said narrow portion.
 4. Photocopying apparatus according to claim 2, wherein said engaging means includes a wheel mounted on said shaft and provided with a gear, and wherein said driving means comprises a chain in mesh with said gear.
 5. Photocopying apparatus according to claim 1, wherein said casing is mounted for being manually returned to its said fixed position after completion of its movement.
 6. Photocopying apparatus according to claim 1, wherein said transparent support member for said thick original is mounted to provide a guide member for a sheet original inserted into said sheet original transporting means.
 7. Photocopying apparatus according to claim 1, wherein said means for releasably holding said casing comprises a projecting member resiliently mounted on said housing, and wherein said casing defines a recessed area for releasably receiving said projecting member. 